Completing the physical installation of a solar photovoltaic system is not the same as proving that it is ready for reliable service. Before handover, technicians need to verify that conductors are correctly identified, protective arrangements are effective and measured performance is consistent with the design and operating conditions.
A disciplined commissioning process protects the client, the installation team and the equipment. It also creates a set of baseline results that can be used during future maintenance and fault-finding.
Begin with documentation and visual inspection
Before applying test instruments, compare the installed system with the approved drawings and equipment schedules. Confirm labels, cable routing, connectors, protective devices, earthing arrangements, isolators and enclosure condition. Look for loose terminations, damaged insulation, unsupported cables, incorrect connector combinations or signs of moisture ingress.
The test plan should reflect the system design, equipment manufacturers’ instructions, applicable standards and local requirements. Appropriate lockout, isolation and personal protective procedures must be established before work begins.
Core electrical measurements
Polarity and continuity
Incorrect polarity can damage equipment and create a serious hazard. Verify conductor identification and polarity before connection. Protective-conductor and bonding continuity should also be checked so the intended fault-current path is confirmed.
Insulation resistance
Insulation testing can reveal cable damage, contamination, moisture or installation defects that may not be visible. Select a test voltage and method appropriate for the PV equipment and ensure sensitive electronics are isolated where required. The Chauvin Arnoux insulation-tester range supports maintenance and installation testing across different voltage and resistance requirements.
Open-circuit voltage and operating voltage
Measured DC voltage helps verify string configuration, polarity and consistency. Results should be compared with design expectations while accounting for module temperature and irradiance. Unusual variation between similar strings deserves investigation before connection to the inverter.
Current measurement
Comparing string or conductor currents can reveal mismatched strings, shading, connection problems or equipment faults. A suitable DC clamp meter allows current to be checked without opening the circuit. The instrument’s measurement category, voltage rating, jaw capacity and DC range must suit the task.
AC-side power and power quality
On the inverter output and at the point of connection, technicians may need to confirm voltage, current, frequency, phase relationships, power, harmonics and energy flow. For detailed diagnostics, instruments such as the CA8336 power-quality analyser can record electrical parameters, alarms, transients and waveforms. For longer energy studies, the PEL103 power and energy logger can record consumption and power values over extended periods.
Record conditions, not only readings
Solar measurements depend on operating conditions. A professional commissioning record should include the date, time, weather, irradiance where available, module temperature, instrument used, configuration tested and measured values. Photographing labels and test points can make the final report easier to understand.
These baseline records become particularly valuable when output changes months or years later. Maintenance teams can compare new readings with commissioning results and distinguish normal environmental variation from deterioration or a developing fault.
The handover is part of the engineering
A strong handover package should include drawings, equipment information, test results, settings, operating instructions, shutdown procedures, warranties and a maintenance plan. The client should understand which checks can be performed routinely and which require a qualified solar or electrical technician.
Chauvin Arnoux Africa supports solar installers, electrical contractors, facilities teams and industrial users with professional test and measurement instruments and local technical guidance through Nocheski Ltd in Tema, Ghana. If you need help selecting instruments for PV commissioning or maintenance, send us your measurement requirement.
Safety note: PV arrays may remain energised whenever exposed to light. Testing and commissioning must be performed by competent personnel using suitable instruments, procedures and personal protective equipment.